why array modifier merging the mesh in each other?
You have an Array modifier with Object Offset. The offset object is an empty. Its rotation value is too low, so your ornement overlaps itself. If you increase the rotation value (RZ) you will avoid overlapping except between first and last.

Your ornement is bent, you should have made sure that it covered 1/4 of a circle (or 1/3 or 1/5 but not 1.2/4, otherwise the overlapping had to happen.

I'm not sure there's any easy solution if you didn't keep a flat version of your ornement. You can try to flatten it back with the Simple Deform modifier / Bend mode (and Z axis). Then try Array + Curve or Array + Simple Deform modifier to make the ornement go 360° with no overlapping, then modify the ornement a bit so that it sticks to the glass.